Tag: Semi Additive Measure

Fact Table | Star Schema:

The centralized table in a star schema is called as FACT table. A fact table typically has two types of columns: those that contain facts and those that are foreign keys to dimension tables. The primary key of a fact table is usually a composite key that is made up of all of its foreign keys.

In the example, “Sales Dollar” is a fact (measure) and it can be added across several dimensions. Fact tables store different types of measures like additive, non additive and semi additive measures.

Measure Types:

Additive – Measures that can be added across all dimensions.

Non Additive – Measures that cannot be added across all dimensions.

Semi Additive – Measures that can be added across few dimensions and not with others.

In the real world, it is possible to have a fact table that contains no measures or facts. These tables are called as Factless Fact tables.